European patent application EP 2 537 612 A2 describes an electric screwdriver with a tool socket whose clamping jaws can be tightened and loosened by a user employing the motor of the electric screwdriver. The electric screwdriver comprises a coupling plate that is connected in the drive train between the motor and the tool socket. The user can move the coupling plate axially and, in a first position for the operational mode, the coupling plate connects the motor to the tool socket. In the second position, the tool socket is uncoupled from the motor, whereby a screw drive is coupled to the motor in order to tighten or loosen the clamping jaws. A through hole with an internal thread is provided in the tool socket for the screw drive, and a rotor with a corresponding mating thread is inserted into said internal thread.
European patent application EP 2 517 811 A1 describes an electric screwdriver with a tool socket. The tool socket is driven by a hollow spindle in which a freely rotatable screw drive is arranged. The screw drive is coupled to the clamping jaw. The hollow spindle can be coupled to the motor whenever desired. This is done by means of an axially movable gear stage that, in a first position, drives the hollow spindle and the screw drive for the operational mode and that, in a second position, only drives the screw drive in order to tighten or loosen the clamping jaws.